3G (“third generation”) networks are widely deployed networks that provide users with a wide range of wireless services including wireless voice telephone, video calls, and broadband wireless data. Examples of 3G technologies include code division multiple access (“CDMA”) 2000 and Evolution-Data Optimized (“EVDO”), which was originally referred to as High Data Rate (“HDR”). CDMA and EVDO refer to the same 3G technology but represent various evolutions of the 3G technology.
The CDMA standard is used for high-speed data-only services. CDMA has been standardized by the Telecommunication Industry Association (“TIA”) as TIA/EIA/IS-856 (see “CDMA2000 High Rate Packet Data Air Interface Specification,” 3GPP2 C.S0024-0, Version 4.0, Oct. 25, 2002, which is incorporated herein by reference. Revision A to this specification has been published as TIA/EIA/IS-856, “CDMA2000 High Rate Packet Data Air Interface Specification,” 3GPP2 C.S0024-A, Version 2.0, June 2005, and is also incorporated herein by reference).
The Evolution-Data Optimized (“EVDO”) standard is used for the wireless transmission of data through radio signals, using multiplexing techniques including CDMA to maximize both individual user's throughput and the overall system throughput. EVDO was designed as an evolution of the CDMA 2000 standard that would support high data rates and could be deployed alongside a wireless carrier's voice services. Initially, the EVDO standard was named High Data Rate (HDR), but was renamed to EVDO after the standard was ratified by the International Telecommunication Union (“ITU”). (See P. Bender, et al., “CDMA/HDR: A Bandwidth-Efficient High-Speed Wireless Data Service for Nomadic Users,” IEEE Communications Magazine, July 2000; and Third Generation Partnership Project 2 (“3GPP2”), “Draft Baseline Text for 1xEV-DO,” Aug. 21, 2000).
Advances in telecommunications technology has brought forth a newly developed class of technologies referred to as 4G (“fourth generation”). Examples of 4G technology include Long-Term Evolution (“LTE”) and Worldwide Interoperability for Microwave Access (“WiMAX”) telecommunications technologies. Generally, 3G networks, such as EVDO, have wide deployment. 4G networks, such as WiMAX and LTE, are initially deployed in a limited area (concentrated in larger cities, for example) and often have limited coverage area.
Prior art systems minimally facilitate a handoff when a mobile device transitions from a network running 3G technology to a network running 4G technology and require the mobile device to close its initial internet protocol (“IP”) connection with the network running the 3G technology, open a new IP connection with the network running 4G technology, and wait for the network running 4G technology to perform a new mobile IP registration to allow connectivity to IP services. This process is commonly referred to as a “hard handoff,” and it is akin to disconnecting a network cable of an IP-enabled device, e.g., a laptop, from a first network and reconnecting it to a different network. During a hard handoff, the mobile device loses the IP connection and access to the IP services as the mobile device transitions between networks. For example, in one prior art system, IP level connectivity is maintained during a handoff, but there is no pre-registration or setup and/or allocation of resources on the target network before the mobile device moves to the target network. This lack of pre-registration and resource allocation leads to long interruption in user services.